The present invention relates to ring-type or circular burners for burning gaseous fuel and particularly burners of the type employed in cooking appliances such as household range top burners. Range top burners are presently manufactured to employ a high voltage arc discharge device for igniting the fuel emanating from the burner ring. Where such spark igniters are employed, it has been found expedient to form the burner ring of conductive metal such that the arc can discharge from a high voltage electrode placed in close proximity to the fuel ports in the burner ring to effect ignition upon arc discharge to the metal ring.
In the present manufacture of cooking range top burners, the primary air-fuel mixture is supplied to the center of the burner ring through an aspirator tube which admixes the air and gaseous fuel prior to discharge through the passages in the burner ring; however, the primary air-fuel mixture is generally too fuel-rich to burn. Therefore a secondary supply of air is required and in so called "open" burners an annular air space is provided about the burner ring to provide additional external air mixing and burning.
In the so called "sealed" burners the range deck closely interfits the burner ring and thus provides a smaller region of the range top into which spill-over or boil-over can fall and accumulate in the burner well but generally requires higher fuel pressures and port velocities to entrain sufficient secondary air for burning. It is apparent that of the two types of burners mentioned above, the sealed burner is the easiest to maintain because the spillage and boil over falls on a flat surface rather than in a burner well.
Heretofore, range top burner rings have been manufactured by stamping and joining thin sheet metal such as stainless steel or by casting light metal such as aluminum. In either type of burner manufacturing, problems have been encountered in providing a simple and easily assembled yet sealed connection to the fuel supply tube in the range top; and, problems have also been encountered in providing for accurate and low cost mounting of the spark igniter about the periphery of the burner ring. It has also been desired to provide for improved secondary fuel-air mixing in the region of the igniter and particularly in the aforesaid sealed burner arrangements.